Resource Allocation Optimization Method for Simultaneous Information and Energy Transfer System

1. A resource allocation optimization method for a Simultaneous Information and Energy Transfer (SIET) system, especially for a multicarrier broadband SIET system, the SIET system being configured to, by a transmitting terminal, transmit a baseband signal comprising an information signal and an energy signal, the optimization method comprising the following steps of: P1: determining, by the transmitting terminal and according to a first optimization target and a first constraint set, an optimal number N E * of carriers for the energy signal and an optimal power P E for the energy signal; wherein: the first optimization target is configured in such a way that: in case that the first constraint set is satisfied, a number of N E carriers of the energy signal is minimal and a power P E of the energy signal is minimal; and the first constraint set contains: C1: the power Q collected by a receiving terminal is greater than or equal to a minimum power P min required by the receiving terminal in a current working mode, that is, Q≥P min ; C2: the energy symbol E*[S 2 E (n)] of energy signal S E (n) on each subcarrier channel is not greater than an energy limit P 1 ; and C3: an average power spectral density on each subcarrier frequency band is less than or equal to a predefined parameter value A; the optimization method further comprising: S11: ranking, depending upon channel quality, subcarrier channel parameters feedback in a descending order; S12: calculating to determine whether the maximum power transmitted on a subcarrier channel which is ranked ahead depending upon the channel quality satisfies the constraint C1, when the constraints C2 and C3 are satisfied; if yes, proceeding to step S14; or otherwise, proceeding to step S13; S13: superposing a next subcarrier channel ranked ahead and determining whether the maximum total power transmitted on the subcarriers superposed satisfies the constraint C1, when the constraints C2 and C3 are satisfied; if yes, proceeding to step S14; or otherwise, repeating step S13; and S14: recording the currently calculated number of subcarrier channels as the optimal number N E * of carriers of the energy signal, and modulating the optimal power P E * of the energy signal satisfying the constraint C1 onto N E * subcarrier channels ranked ahead depending upon the channel quality.

2. The resource allocation optimization method of claim 1 , further comprising: based on the optimal number N E * of carriers of the energy signal and the optimal power P E * of the energy signal, by the transmitting terminal, obtaining the optimal number N I * of carriers of the information signal and the optimal power P I * of the information signal; and wherein, N I *=N−N E * and P I *=P−P E *, N is total number of carriers.

3. The resource allocation optimization method of claim 2 , further comprising: by a convex optimization algorithm, determining an optimal information signal power allocation set {E*[S 2 I (n)]} and an optimal information signal subcarrier allocation set Sc I *, wherein n=1, 2, . . . , N I .

4. The resource allocation optimization method of claim 3 , further comprising: determining an optimal information transmission rate R* according to the optimal information signal power allocation set {E*[S 2 I (n)]} and the optimal information signal subcarrier allocation set Sc I *, wherein: R * = B s * ∑ n = 1 N I * ⁢ log 2 ⁡ ( 1 +  h i  2 ⁢ E i * σ 2 ) ; wherein n=1, 2, . . . , N I *, σ 2 is an average noise power, B is the channel bandwidth of each subcarrier, h i is the channel parameter vector for the i th subcarrier channel and E i is the energy for the i th subcarrier channel.

5. The resource allocation optimization method of claim 1 , wherein the first constraint set further contains: C4: the sum of energy signal power on subcarriers is less than or equal to the total power of the energy signal.

6. The resource allocation optimization method of claim 1 , wherein, in the constraint C1, the working mode of the receiving terminal comprises a normal working mode, an energy consumption mode and an energy storage mode.